But it can easily be argued that it's been a zero-sum game, where one actor has been forced to use more targeted ads because others have been more efficient (cheaper) by doing so. It's not like ads spending has increased; unless you're arguing that consumption has increased due to targeted/invasive ads?
It is difficult for me to see how it would be zero sum. Instead it seems very likely to me that the total amount spent by users online is higher with invasive ads than non-invasive ones: if no ad you see is relevant to you then you are less likely to buy anything online at all.
There's an argument I've seen - no idea whether it's correct - that users acclimatise to new advertising technology and eventually regress back to the mean. I suppose this would mean that newer and more invasive ads cause a spike in consumer spending, which drops over time until the next innovation.
I've never seen someone make that argument for better targeting, which is what they're saying cookies enable. You're not going to acclimate to being more interested in the ads you're seeing.
The argument for better targeting is simple: targeting works (whether directly or just through being a novelty), and those who engage in it get ahead of those who don't.
The argument for getting used to ads is mostly psychology/neuroscience.
